Alternatively, could I use this Koolance Quad splitter:
in this manner?
That would probably be the cleanest solution, if it'll work. Well, apart from running the pumps in series, which would eliminate the need for splitting the fillport.
As for loading it all up, well, it gets quite toasty with Flight Simulator X (8 threads + GPU) and Grand Theft Auto IV (3 threads + GPU), or if I'm multitasking (Photoshop=GPU+CPU, Browsers=CPU, VMs=CPU). With that in mind, would you still suggest pumps in series, or as separate loops?